From: Colin Ian King colin.king@canonical.com

stable inclusion from stable-v4.19.213 commit 7f642b93710b6b1119bdff90be01e6b5a2a5d669 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9RB7E CVE: CVE-2021-47445

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...

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commit 2133c4fc8e1348dcb752f267a143fe2254613b34 upstream.

The initialization of pointer dev dereferences pointer edp before edp is null checked, so there is a potential null pointer deference issue. Fix this by only dereferencing edp after edp has been null checked.

Addresses-Coverity: ("Dereference before null check") Fixes: ab5b0107ccf3 ("drm/msm: Initial add eDP support in msm drm driver (v5)") Signed-off-by: Colin Ian King colin.king@canonical.com Reviewed-by: Dmitry Baryshkov dmitry.baryshkov@linaro.org Link: https://lore.kernel.org/r/20210929121857.213922-1-colin.king@canonical.com Signed-off-by: Rob Clark robdclark@chromium.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Liu Chuang liuchuang40@huawei.com --- drivers/gpu/drm/msm/edp/edp_ctrl.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/msm/edp/edp_ctrl.c b/drivers/gpu/drm/msm/edp/edp_ctrl.c index 7c72264101ff..2589b23c4131 100644 --- a/drivers/gpu/drm/msm/edp/edp_ctrl.c +++ b/drivers/gpu/drm/msm/edp/edp_ctrl.c @@ -1090,7 +1090,7 @@ void msm_edp_ctrl_power(struct edp_ctrl *ctrl, bool on) int msm_edp_ctrl_init(struct msm_edp *edp) { struct edp_ctrl *ctrl = NULL; - struct device *dev = &edp->pdev->dev; + struct device *dev; int ret;

if (!edp) { @@ -1098,6 +1098,7 @@ int msm_edp_ctrl_init(struct msm_edp *edp) return -EINVAL; }

+ dev = &edp->pdev->dev; ctrl = devm_kzalloc(dev, sizeof(*ctrl), GFP_KERNEL); if (!ctrl) return -ENOMEM;